The case dates back to 1999 when the University of California and Eolas Technologies sued Microsoft, claiming that Internet Explorer was infringing a patent for a method that allows web browsers to access interactive application programs.
The patent, issued to the University in 1998, has been licensed exclusively to Eolas since 1994. But according to Eolas' lawyer Martin Lueck:
"Facing competition from Netscape Navigator in the mid-1990s, Microsoft updated its Explorer browser by using Eolas' technology and subsequently bundled it with all of its Windows operating systems since 1995."
In August last year a jury agreed, and awarded damages of $520.6 million plus interest to Eolas. Microsoft is in the process of appealing the verdict, but in October detailed changes it is to make to the browser to remove any possible future infringement.
The case has caused considerable furore among the browser community as, if upheld, the patent seems likely to be of widespread applicability. Such is the concern that the W3C, an international standards-setting body for the internet, stepped into the dispute at the end of October when its director, Tim Berners-Lee, wrote to the US Patent and Trademark Office asking that the patent – known as patent '906 – be declared invalid.
In November the USPTO agreed to re-examine the patent.
As part of the appeals process, in October both Eolas and Microsoft filed motions with the US District Court in Chicago. Eolas asked the court to grant an injunction preventing Microsoft from distributing Internet Explorer, where it infringed on Eolas' patent.
For its part, Microsoft asked the court to grant a new trial on the dispute claiming, among other things, that in the original trial the court had refused to allow evidence of prior art – technology created before the granting of the Eolas patent – that would have invalidated the patent.
On Wednesday the court upheld the original jury verdict and issued an injunction against the distribution of Internet Explorer, although the injunction has been put on ice until the appeals process has been completed.
Microsoft was not granted its re-trial, or even a delay in the decision, despite the ongoing re-examination by the USPTO. According to a report in eWeek, Judge James Zagel wrote in his opinion:
"re-examination was not reason enough to delay his decision or the appeals process and that such a delay would more significantly hurt Eolas if the patent ultimately remains valid."
Microsoft says it will appeal within the required 30 days. Spokesman Lou Gellers told CNET News.com:
"We remain confident that on appeal, when people hear this though, they will see that – as we claimed – the patent is not valid."
He added:
"We don't think we violated anything even if it were valid."
Michael Doyle, founder of Eolas told eWeek:
"If Microsoft can't read the writing on the wall now then they need a new eye doctor."